1. Field of the Invention
The present invention pertains to broad spectrum antimicrobial compositions suitable for use in the protection of paints and paint films, wood products, leather, metal working fluids, mineral slurries, inks, dispersions and other wet state industrial products or processes from spoilage resulting from the growth of microorganisms, especially fungi and algae. The antimicrobial compositions of this invention include mixtures comprising 2-(methoxycarbonylamino)benzimidazole, an iodopropynyl compound and, where desirable, an algicide. These combinations are especially useful in protecting stucco, paint, coatings, Exterior Insulation Finish Systems (EIFS), leather, wood products, and construction materials such as tape-joint compounds, caulks, sealants, and adhesives.
2. Description of the Background
Substrates of all types and water-containing compositions and formulations, when exposed to common environmental conditions are prone to attack, spoilage and various kinds of destruction by a variety of species of microorganisms including fungi, yeast, bacteria and algae. As a result, there has always been a great need for effective and economical means to protect, for extended periods of time, commercial compositions and formulations from the deterioration and destruction caused by such microorganisms.
Materials which need protection against such microorganisms include, for example, materials such as paints and other coating formulations, surfactants, proteins, starch-based compositions, inks, emulsions and resins, stucco, concrete, stone, wood, adhesives, caulks, sealants, leather, and spin finishes. Other important commercial materials such as polymer dispersions or aqueous latex paints containing polyvinyl alcohol, polyacrylates or vinylpolymers, thickener solutions containing cellulose derivatives, clay and mineral suspensions and metal working fluids, also are prone to degradation by the action of objectionable microorganisms which can spoil and significantly impair the usefulness of such compositions. Such degradation may produce, inter alia, changes in pH values, gas formation, discoloration, the formation of objectionable odors, and/or changes in rheological properties.
Antimicrobials are also important during the processing of materials. For example animal skins are susceptible to attack by microorganisms both prior to and after the tanning process. Prior to the tanning process, bactericides are used in the brine solutions to prevent bacteria from damaging the hide grain. After the tanning process, the so called wet blue hides are subject to fungal attack during storage or transport and fungicides are used to inhibit this fungal growth. Antimicrobials can also be used in the fat liquors and leather finishing products to prevent the growth of bacteria, fungi and yeast.
A great deal of effort has gone into developing a wide variety of materials which, to various degrees, are effective in retarding or preventing the growth of, and accompanying destruction caused by, such microorganisms in a variety of circumstances. Such antimicrobial materials included halogenated compounds, organometallic compounds, quaternary ammonium compounds, phenolics, metallic salts, heterocyclic amines, formaldehyde adducts, organosulfur compounds and the like.
No single organic antimicrobial compound is able to provide protection against all microorganisms or is suitable for all applications. In addition to such limitations concerning efficacy, other limitations may restrict the usefulness of certain antimicrobials. For example the stability, physical properties, toxicological profile, regulatory considerations, economic considerations or environmental concerns may render a particular ingredient unsuitable for a particular use. There is a need, therefore, to constantly develop new combinations that will offer broad spectrum protection from a variety of needs.
A judicious choice of combinations may provide a way to maximize benefits while at the same time minimize problems. Ideally, a combination wherein the antimicrobial activity is enhanced while the less desirable properties are suppressed can provide a superior product. The task is to find such combinations that will provide protection against a wide variety of problem microorganisms, will not adversely affect the product to be protected, will maintain its integrity for an extended period of time, and will not have any adverse effect on health or the environment.
While some combinations of 2-(methoxcarbonylamino)benzimidazole, 3-iodo-2-propynyl-butyl carbamate and algicides have been reported, the novel combinations of this invention, combinations which demonstrate the kind of unexpected properties and activities that allow them to be used in an unanticipated way, have not been reported.